Ceramic honeycombs, for example cordierite or aluminum titanate honeycombs, are made by extrusion of a ceramic paste. The ceramic paste is prepared by mixing dry raw materials followed by the addition, with further mixing, of liquid components and plasticizing the resulting mixture using an augur or twin screw mixing system. After plasticizing, the ceramic paste is pushed through an extruder die to form a honeycomb “green body” that is further processed. The overall process can be summarized as providing a plasticized ceramic honeycomb precursor batch material comprising inorganic ceramic-forming components, optional pore forming materials (for example a starch or graphite material), liquid components (for example, water), lubricating materials (to aid in extrusion) and binders; plasticizing the mixture; forming a green body having the desired shape, size and cells density from the plasticized ceramic precursor batch material; optionally drying the green body to remove excess moisture and prevent slumping during firing; and firing the dried green body under conditions sufficient to convert the green body into a ceramic honeycomb. Depending on the choice of inorganic materials, the fired honeycomb can be a cordierite or aluminum titanate honeycomb. In the above process one problem that is frequently encountered is the plugging of the die during the extrusion process, particularly when ultra-thin wall honeycomb substrates are formed. The present invention presents a solution to the plugging process.